Prassinos was born in Istanbul, Ottoman Empire (now Turkey) in 1916, the son of Victorine and Lysandre Prassinos. In 1922, at the age of six, he immigrated to France with his family, who had escaped the brutal persecution of Greeks and other ethnic minorities by the Ottoman government. Prassinos became a naturalized French citizen in 1949.
He attended the Sorbonne in Paris beginning in 1932 and briefly trained in the studio of the French painter Clement Serveau (1886–1972).
Through his father's literary interests Prassinos became acquainted with Surrealism, meeting Paul Eluard, André Breton, Salvador Dalí, Man Ray. Max Ernst, Marcel Duchamp and others in 1934, and decided to become an artist. From 1932 to 1936 he worked in a Surrealist style, introducing procedures of automatism and formal ambiguities that he retained in his later work.
During the period 1942 to 1950 he met Raymond Queneau and Albert Camus and produced work for Editions Gallimard.
Prassinos' work is found in major art museums in Europe and North America, including the Stedelijk Museum, Amsterdam; Musée National d'Art Moderne, Paris; Kunsthalle Bremen, Germany; Victoria and Albert Museum, London; Museum of Modern Art, New York; Metropolitan Museum of Art, New York; Art Institute of Chicago, and others.
Prassinos died at his home in Eygalières, France on 23 October 1985. After his death, a donation of 800 of the artist's works was made to the French state. The "Donation Mario Prassinos" collection is housed in the Chapel of Notre-Dame de Pitié (also called Notre-Dame des Sept Douleurs) in Saint Remy de Provence, France.
His sister Gisèle Prassinos (born 1920) is a noted surrealist writer.Wikipedia